1. Field of the Invention
The present invention relates to a recording tape cartridge, and more particularly to a recording tape cartridge including a case that houses a single reel onto which is wound recording tape such as magnetic tape mainly used as a recording and playback medium for computers and the like.
2. Description of the Related Art
Conventionally, magnetic tape cartridges have been known which include a case that houses a single reel onto which is wound magnetic tape used as a data recording and playback medium for computers and the like. A leader member, such as a leader block, a leader pin, or a leader tape, is disposed on a leading end of the magnetic tape. A pullout mechanism disposed in a drive device pulls out the leader member from the magnetic tape cartridge, and the magnetic tape fixed to the leader member is wound onto a take-up reel of the drive device.
Japanese Patent Application Publication (JP-A) No. 2004-348863 discloses a recording tape cartridge that includes a plate spring (lock spring) that holds both end portions of the leader pin. Because both end portions of the leader pin are held by the plate spring, the leader pin is prevented from coming out even if a collision acts on the recording tape cartridge, such as a collision resulting from the recording tape cartridge being inadvertently dropped. JP-A No. 2004-47057 discloses a recording tape cartridge where a support point protrusion serving as a support point when the lock spring flexes is disposed inside the case, so that the pressing force of the lock spring is stabilized by the support point protrusion.
However, because the lock spring is formed by bending a metal plate or a metal rod, sometimes, due to variations or the like in the bending precision, the lock spring does not contact the support point protrusion when the lock spring is attached to the case. That is, there are variations in the pressing force of the lock spring—that is, the pullout resistance force of the leader pin—between when the lock spring contacts the support point protrusion and when the lock spring does not contact the support point protrusion.
When, for example, the machining precision of the lock spring is raised in order to eliminate this drawback, there is the potential for the machining range to become narrow and for the cost to increase. Also, when the support point protrusion is eliminated and the lock spring itself is made compact, it becomes difficult to attach the lock spring to the case.